DNA found in the mitochondrion of a cell differs in structure and is separate from the DNA found in the cell nucleus. Mitochondrial DNA, or mtDNA, exists as a circular loop of double-stranded DNA rather than the linear form found in nuclear DNA. However,

Unlike nuclear DNA, mtDNA is Â inherited solely from the mother. (Mitochondria are predominantly from the motherâs egg and not from the fatherâs sperm.) Therefore, mtDNA sequences or orders of nucleotides generally remain constant over many generation